From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29625 invoked by alias); 20 Aug 2003 02:30:09 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 29612 invoked from network); 20 Aug 2003 02:30:09 -0000 Received: from unknown (HELO nevyn.them.org) (66.93.172.17) by sources.redhat.com with SMTP; 20 Aug 2003 02:30:09 -0000 Received: from drow by nevyn.them.org with local (Exim 4.20 #1 (Debian)) id 19pIjd-0000GY-KI; Tue, 19 Aug 2003 22:30:05 -0400 Date: Wed, 20 Aug 2003 02:30:00 -0000 From: Daniel Jacobowitz To: Jimi Xenidis Cc: Kevin Buettner , gdb-patches@sources.redhat.com, Andrew Cagney Subject: Re: Powerpc and software single step Message-ID: <20030820023005.GA1004@nevyn.them.org> Mail-Followup-To: Jimi Xenidis , Kevin Buettner , gdb-patches@sources.redhat.com, Andrew Cagney References: <16185.27333.689024.383508@kitch0.watson.ibm.com> <1030819175512.ZM31220@localhost.localdomain> <20030819191300.GA24336@nevyn.them.org> <16194.42367.562777.115053@kitch0.watson.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <16194.42367.562777.115053@kitch0.watson.ibm.com> User-Agent: Mutt/1.5.1i X-SW-Source: 2003-08/txt/msg00328.txt.bz2 On Tue, Aug 19, 2003 at 06:32:31PM -0400, Jimi Xenidis wrote: > >>>>> "DJ" == Daniel Jacobowitz writes: > > DJ> On Tue, Aug 19, 2003 at 10:55:13AM -0700, Kevin Buettner wrote: > > >> 2) Why is ``ppc_linux_single_step_mode'' an extern in tm-linux.h? I > >> would really prefer that it be local to ppc-linux-tdep.c. If > >> there's some compelling reason for it to not be local, then we can > >> discuss adding it to ppc-tdep.h. > > DJ> Could we do this slightly differently? SOFTWARE_SINGLE_STEP_P is used > DJ> in two non-platform-specific files: infptrace.c for a sanity > DJ> check, > This sanity check is wierd, does it expect PT_STEP to be defined _and_ > not supported? It does happen. MIPS/Linux does that sometimes, so does anything else where PT_STEP is restricted or broken. > DJ> Why not add a hook to check there which lets the user use software > DJ> single step? It'll require playing with the target macros; we'd need > DJ> something like: > DJ> SOFTWARE_SINGLE_STEP - perform software single step > DJ> SOFTWARE_SINGLE_STEP_P - SOFTWARE_SINGLE_STEP available > DJ> SOFTWARE_SINGLE_STEP_ONLY_P - no hardware singlestep available > DJ> (check that in infptrace instead of SOFTWARE_SINGLE_STEP_P?) > > I believe that this increases the complexity of the solution. > On first inspection it looks like the proper solution is simply > abstracting single step and let the code do the appropriate > thing.. but that could easily break older targets that are not > actively maintained, but I yield to senior heads on this. > > My first attempt was to drag ppc/rs6000 into the gdbarch world and > drop the #defines all together. However, the test (_P) rotuine tests > a function pointer and it was not readily apparent how to have a set > command set a function pointer or actually run code to do so. Perhaps > pairing it with a gdbarch boolean? I'm not sure what you mean. I actually left out something from my example; above would be macros set by the architecture, and there would be a USE_SOFTWARE_SINGLE_STEP_P that would be user controlled but default based the architecture. -- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer